SDM-8AO
Expansion Module – 8 analog outputs
Version 1.3 User Manual
Manufactured for
SDM-8AO
User Manual
Expansion Module – 8 analog outputs
User Manual Version 1.3 2 z 17
Thank you for choosing our product.
This manual will help you with proper support and proper operation of the device.
The information contained in this manual have been prepared with utmost care by our
professionals and serve as a description of the product without incurring any liability for
the purposes of commercial law.
This information does not release you from the obligation of own judgment and
verification.
We reserve the right to change product specifications without notice.
Please read the instructions carefully and follow the recommendations contained
therein.
WARNING!
Failure to follow instructions can result in equipment damage or impede
the use of the hardware or software.
SDM-8AO
User Manual
1. Safety rules
•Before first use, refer to this manual
•Before first use, make sure that all cables are connected properly
•Please ensure proper working conditions, according to the device specifications
(eg: supply voltage, temperature, maximum power consumption)
•Before making any modifications to wiring connections, turn off the power supply
2. Module Features
2.1. Purpose and description of the module
The SDM-8AO module has a set of 8 analog outputs that could work as a current
output (0-20mA or 4-20mA) or as a voltage output (0-10V). Setting the output curent
or voltage value is done via RS485 (Modbus protocol), so you can easily integrate the
module with popular PLCs, HMI or PC equipped with the appropriate adapter.
This module is connected to the RS485 bus with twisted-pair wire.
Communication is via MODBUS RTU or MODBUS ASCII. The use of 32-bit ARM
core processor provides fast processing and quick communication. The baud rate is
configurable from 2400 to 115200.
The module is designed for mounting on a DIN rail in accordance with
DIN EN 5002.
The module is equipped with a set of LEDs used to indicate the status of inputs
and outputs useful for diagnostic purposes and helping to find errors.
Module configuration is done via USB by using a dedicated computer program.
You can also change the parameters using the MODBUS protocol.
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2.2. Technical Specifications
Power Supply
Voltage 10-30 VDC; 10-28VAC
Maximum Current*DC: 52 mA @ 24VDC
AC: 62 mA @ 24VAC
Maximum power consumption DC: 1,25W; AC: 1,5VA
Outputs
No of outputs 8
Voltage output 0V do 10V ( resolution 1.5mV)
Current output 0mA do 20mA ( resolution 5μA)
Current output 4mA do 20mA (value in ‰ – 1000 steps)
(resolution 16μA)
Measurement resolution 12 bits
ADC processing time 16ms / channel
Temperature Work -10 °C - +50°C
Storage -40 °C - +85°C
Connectors
Power Supply 2 pins
Communication 3 pins
Outputs 2x 10 pins
Configuration Mini USB
Size
Height 110 mm
Length 62 mm
Width 88 mm
Interface RS485 Up to 128 devices
* Maximum current with active Modbus transmission, all inputs connected and all output active
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2.3. Dimensions of the product
Look and dimensions of the module are shown below. The module is mounted
directly to the rail in the DIN industry standard. Power connectors, communication and
IOs are at the bottom and top of the module. USB connector configuration and
indicators located on the front of the module.
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35
110
4
8
, 5
6
2
6
42,3
91
110
88
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3. Communication configuration
3.1. Grounding and shielding
In most cases, IO modules will be installed in an enclosure along with other
devices which generate electromagnetic radiation. Examples of these devices are relays
and contactors, transformers, motor controllers etc. This electromagnetic radiation can
induce electrical noise into both power and signal lines, as well as direct radiation into
the module causing negative effects on the system. Appropriate grounding, shielding
and other protective steps should be taken at the installation stage to prevent these
effects. These protective steps include control cabinet grounding, module grounding,
cable shield grounding, protective elements for electromagnetic switching devices,
correct wiring as well as consideration of cable types and their cross sections.
3.2. Network Termination
Transmission line effects often present a problem on data communication
networks. These problems include reflections and signal attenuation.
To eliminate the presence of reflections from the end of the cable, the cable must
be terminated at both ends with a resistor across the line equal to its characteristic
impedance. Both ends must be terminated since the direction of propagation is bi-
directional. In the case of an RS485 twisted pair cable this termination is typically
120 Ω.
3.3. Setting Module Address in RS485 Modbus Network
The following table shows how to set switch to determine the address of the
module. The module address is set with the switches in the range of 0 to 127. Addresses
From 128 to 255 can by set via RS485 or USB.
Switch Address
SW1 +1
SW2 +2
SW3 +4
SW4 +8
SW5 +16
SW6 +32
SW7 +64
Ex. if switches 1, 3 and 5 are on than module addres is:
Address = 1 + 4 + 16 = 21
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3.4. Types of Modbus Registers
There are 4 types of variables available in the module
Typ
e
Beginning
address Variable Access Modbus
Command
1 00001 Digital Outputs Bit
Read & Write 1, 5, 15
2 10001 Digital Inputs Bit
Read 2
3 30001 Input Registers Registered
Read 3
4 40001 Output Registers Registered
Read & Write 4, 6, 16
3.5. Communication settings
The data stored in the modules memory are in 16-bit registers. Access to
registers is via MODBUS RTU or MODBUS ASCII.
3.5.1. Default settings
You can restore the default configuration by the switch SW8 (see 3.5.2 - Restore
the default configuration)
Baud rate 19200
Parity No
Data bits 8
Stop bits 1
Reply Delay [ms] 0
Modbus Type RTU
3.5.2. Restore the default configuration
To restore the default configuration:
•turn off the power
•turn on the switch SW8
•turn on the power
•when power and communication LED start blinking alternately than turn off the
switch SW8
Caution! After restoring the default configuration all values stored in the registers will
be cleared as well.
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3.5.3. Configuration registers
Modbus Dec Hex Name Values
40003 2 0x02 Baud rate
0 – 2400
1 – 4800
2 – 9600
3 – 19200
4 – 38400
5 – 57600
6 – 115200
other – value * 10
40005 4 0x04 Parity
0 – none
1 – odd
2 – even
3 – always 1
4 – always 0
40004 3 0x03 Stop Bits LSB 1 – one stop bit
2 – two stop bits
40004 3 0x03 Data Bits MSB 7 – 7 data bits
8 – 8 data bits
40006 5 0x05 Response delay Time in ms
40007 6 0x06 Modbus Mode 0 – RTU
1 – ASCII
3.5.4. Watchdog function
This 16-bit register specifies the time in milliseconds to watchdog reset. If module does
not receive any valid message within that time, all Digital and Analog Outputs will be
set to the default state.
This feature is useful if there is an interruption in data transmission and for security
reasons. Output states must be set to the appropriate state in order to assure the safety
of persons or property.
The default value is 0 milliseconds which means the watchdog function is disabled.
Range: 0-65535 ms
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4. Switches
Switch Function Description
1 Module address +1
Setting module address from 0 to 127
2 Module address +2
3 Module address +4
4 Module address +8
5 Module address +16
6 Module address +32
7 Module address +64
8 Restoring default settings Restoring default settings
(see 3.5.2 - Restore the default configuration).
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ON
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5. Front panel removing
To remove the panel and gain access to the switch, you must pry open the panel
using a thin tool (eg a small screwdriver) as in the picture below.
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6. Indicators
Indicator Description
Power supply LED indicates that the module is correctly powered.
Communication The LED lights up when the unit received the correct packet
and sends the answer.
Outputs state LED indicates that the output is on.
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1 2 3 4 5 6 7 8
ON
Communication
mini USB
configuration
connector
Power supply
Output 1 – 4 state
Output 5 – 8 state
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7. Module Connection
7.1. Analog outputs
Current output Voltage output
7.2. Power supply of analog outputs
AC / DC
7.3. Communication, power supply
Communication Power supply, DC Voltage
24VDC
Power supply, AC voltage
24VAC
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8. Setting output mode
Each of outputs can be configured as a voltage outputs or a current outputs. To
change the operating mode in addition to configuration changes by using the program or
via RS485, also set the jumpers inside the module as shown below.
Jumper Description
Current output
(default)
Voltage output
9. Opening the housing
1. Remove the clip by pressing it and moving toward the center of the housing
2. Separate the housing gently tilting the clamps using a thin tool.
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10. Modules Registers
10.1. Registered access
Modbus Dec Hex Register Name Access Description
30001 0 0x00 Version/Type Read Version and Type of the device
30002 1 0x01 Switches Read Switches state
40003 2 0x02 Baud rate Read & Write RS485 baud rate
40004 3 0x03 Stop Bits & Data Bits Read & Write No of Stop bits & Data Bits
40005 4 0x04 Parity Read & Write Parity bit
40006 5 0x05 Response Delay Read & Write Response delay in ms
40007 6 0x06 Modbus Mode Read & Write Modbus Mode (ASCII or RTU)
40009 8 0x08 Watchdog Read & Write Watchdog
40033 32 0x20 Received packets LSB Read & Write No of received packets
40034 33 0x21 Received packets MSB Read & Write
40035 34 0x22 Incorrect packets LSB Read & Write No of received packets with error
40036 35 0x23 Incorrect packets MSB Read & Write
40037 36 0x24 Sent packets LSB Read & Write No of sent packets
40038 37 0x25 Sent packets MSB Read & Write
30051 50 0x32 Outputs Read Bit is set if value ≠ 0
40053 52 0x34 Analog output 1 Read & Write Value of analog output:
in mV for voltage output
(max 10240)
in μA for current output
0 - 20mA (max 20480)
in ‰ for current output
4-20mA (max 1000)
40054 53 0x35 Analog output 2 Read & Write
40055 54 0x36 Analog output 3 Read & Write
40056 55 0x37 Analog output 4 Read & Write
40057 56 0x38 Analog output 5 Read & Write
40058 57 0x39 Analog output 6 Read & Write
40059 58 0x3A Analog output 7 Read & Write
40060 59 0x3B Analog output 8 Read & Write
40061 60 0x3C Default output 1 value Read & Write
Default value of output set when
power is on or when watchdog reset
occurs
40062 61 0x3D Default output 2 value Read & Write
40063 62 0x3E Default output 3 value Read & Write
40064 63 0x3F Default output 4 value Read & Write
40065 64 0x40 Default output 5 value Read & Write
40066 65 0x41 Default output 6 value Read & Write
40067 66 0x42 Default output 7 value Read & Write
40068 67 0x43 Default output 8 value Read & Write
40069 68 0x44 Output 1 setting Read & Write Setting of output mode:
70 69 0x45 Output 2 setting Read & Write
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Modbus Dec Hex Register Name Access Description
0 – output disable
1 – voltage output
2 – current output 0-20mA
3 – current output 4-20mA
40071 70 0x46 Output 3 setting Read & Write
40072 71 0x47 Output 4 setting Read & Write
40073 72 0x48 Output 5 setting Read & Write
40074 73 0x49 Output 6 setting Read & Write
40075 74 0x4A Output 7 setting Read & Write
40076 75 0x4B Output 8 setting Read & Write
10.2. Bit access
Modbus
Address
Dec
Address
Hex
Address
Register
name Access Description
801 800 0x320 Output 1 Read
If voltage or current is greater than 0 then
according bit is set.
802 801 0x321 Output 2 Read
803 802 0x322 Output 3 Read
804 803 0x323 Output 4 Read
805 804 0x324 Output 5 Read
806 805 0x325 Output 6 Read
807 806 0x326 Output 7 Read
808 807 0x327 Output 8 Read
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11. Configuration software
Modbus Configurator is software that is designed to set the module registers
responsible for communication over Modbus network as well as to read and write the
current value of other registers of the module. This program can be a convenient way to
test the system as well as to observe real-time changes in the registers.
Communication with the module is done via the USB cable. The module does
not require any drivers.
Configurator is a universal program, whereby it is possible to configure all
available modules.
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Table of Contents
1. Safety rules......................................................................................................................................3
2. Module Features..............................................................................................................................3
2.1. Purpose and description of the module....................................................................................3
2.2. Technical Specifications..........................................................................................................4
2.3. Dimensions of the product.......................................................................................................5
3. Communication configuration.........................................................................................................6
3.1. Grounding and shielding..........................................................................................................6
3.2. Network Termination...............................................................................................................6
3.3. Setting Module Address in RS485 Modbus Network..............................................................6
3.4. Types of Modbus Registers......................................................................................................7
3.5. Communication settings..........................................................................................................7
3.5.1. Default settings................................................................................................................7
3.5.2. Restore the default configuration.....................................................................................7
3.5.3. Configuration registers.....................................................................................................8
3.5.4. Watchdog function...........................................................................................................8
4. Switches...........................................................................................................................................9
5. Front panel removing....................................................................................................................10
6. Indicators.......................................................................................................................................11
7. Module Connection.......................................................................................................................12
7.1. Analog outputs.......................................................................................................................12
7.2. Power supply of analog outputs.............................................................................................12
7.3. Communication, power supply..............................................................................................12
8. Setting output mode.......................................................................................................................13
9. Opening the housing......................................................................................................................13
10. Modules Registers.......................................................................................................................14
10.1. Registered access.................................................................................................................14
10.2. Bit access.............................................................................................................................15
11. Configuration software................................................................................................................16
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Manufactured for:
Aspar s.c.
ul. Oliwska 112
80-209 Chwaszczyno
POLAND
www.ampero.eu
tel. +48 58 351 39 89; +48 58 732 71 73
Output No
Current
output
(default)
Voltage
output
1
2
3
4
5
6
7
8
/
